Numerous studies have demonstrated that frontal activation patterns of the cerebral hemispheres differ during the experience of positive versus. negative emotions during waking. Furthermore, there are stable patterns of waking prefrontal activation asymmetry which are associated with temperament and pathological states such as depression. The purpose of the proposed study is to determine whether frontal activation patterns during sleep are correlated with patterns during wakefulness and/or affective content of dreaming. These studies should increase our understanding of the neural regulation of mood.